Web frontend and supporting services for lance.blue

feat: cut every button as a notched plate master

The site's stamped shape - top-left and bottom-right corners taken off - was written out once per control on the daily card and the waiting screen. It is now the default for every button and for anything wearing .plate, with tiles, round icons, pills, menu rows and mode cards opting out. A clipped control cannot wear an outlined focus ring, so plates take an inset one and the opt-outs keep the outline; a quiet button is filled rather than outlined, because a cut edge left its border broken.